This is precisely what a senior does for a junior: review their code. Not just for it's ability to run, but what resources it uses, which resources can be trust

This is precisely what a senior does for a junior: review their code. Not just for it's ability to run, but what resources it uses, which resources can be trusted, and what other resources are available. That's what makes the experience novel: it's a junior that knows all the languages, all the services, all the idioms, but who has zero judgement about whether to use them.